Do cows contribute more to atmospheric warming than cars?

Question

In this article and many others, I read that cows are contributing to the climate change more than cars in releasing CO2.

A United Nations report has identified the world's rapidly growing herds of cattle as the greatest threat to the climate, forests and wildlife.

If this is true humans shouldn't be blamed for the climate change. I understand we grow them for meat so it's again us. But if we would let the cows overpopulate we would end up with the same result.

You should make this question more clear. With cows, methane is a major issue. So you have to be clear if you mean purely CO2, or gases weighted by atmospheric forcing. And do you mean all cars versus all cows world-wide, or just in New Zealand? — DavePhD, Jun 23 '17 at 19:18
It's not that cows would be contributing to climate change by growing in population if we weren't eating them; they would just not exist. Cows are domesticated animals and would not survive without the agricultural supports we give them. Raising cows contributes to global warming through methane and deforestation. — antlersoft, Jun 23 '17 at 19:22
@antlersoft India has the most cows. They are not usually eaten, but they definitely exist. — DavePhD, Jun 23 '17 at 19:27
@Grasper - For updated poster, note that while methane 504 lbs of methane in the atmosphere has heat trapping power of nearly 12,000 lbs of C02, methane doesn't stay in the atmosphere very long compared to CO2, so the total heat trapped by the incremental CO2 will be greater. Both agriculture and fossil-fuel use contribute to global warming; a significant part of the impact of agriculture isn't emissions per se but the attendant deforestation, which degrades a valuable carbon sink. — antlersoft, Jun 23 '17 at 19:56
The question as stated is a bit disjointed. The comparison of cattle production of methane vs. automobile production of CO2 has no direction connection to the issue of whether humans are responsible for climate change, since there are many other sources of greenhouse gases, as noted in Kevin Fee's answer. — jeffronicus, Jun 23 '17 at 20:02
The title and the body currently have different claims. Do cows produce more CO2 than cars? Straight forward. Do cows contribute more to greenhouse warming than cars? Much more complicated, as you have to look at the whole cycle. Cows make CO2 from digesting grass, which removes CO2 from the atmosphere to grow. Cars make CO2 from fossil fuels, which were created millions of years ago. That carbon was not in the atmosphere for a long time. And of course methane is its own issue. — Brythan, Jun 24 '17 at 03:32
@antlersoft: "Cows" - that is, bovines of various species - would certainly exist if people didn't raise them, unless of course people made a concerted effort to wipe them out. For instance, the domestic cow is closely related enough to the wild buffalo that they can interbreed. See e.g. beefalo. And there used to be many millions of buffalo inhabiting North America. Same for wild bovines in Africa, Asia, &c. — jamesqf, Jun 24 '17 at 04:30
The currently-linked image does not claim that cows produce more CO2 than cars. Indeed, it does not claim that cows produce any CO2 whatsoever. You should either find a new source making the same claim as the text of your question, or rewrite your question to match the claim actually made by your source. — Dave Sherohman, Jun 24 '17 at 08:10
@jamesqf they might exist, but if we as a species released all of the cattle into the wild and neglected them (perhaps because we were all dead or had entirely abandoned the planet) you'd see the cow populations drop rapidly, through starvation, predation, disease, and so forth. — Ben Barden, Jun 26 '17 at 16:17
@Ben Barden: You might see a drop due to domesticated cattle not knowing how to live in the wild, but the survivors would soon reproduce and increase the population again, especially if humans keep eliminating predators. Consider wild/feral horses in the US west as a parallel case. You also see plenty of wild bovines (and other creatures filling similar ecological niches) in places like the African savannah, where there's little or no human support. — jamesqf, Jun 27 '17 at 05:10
@jamesqf - it's more than that. They don't know how to live in the wild, they've been adapted for generations to be better meat/milk producers rather than being more competitive (especially pertinent for food-efficiency and starvation), they're far too concentrated, and will quickly strip whatever area they're in of food, leading to a starvation cycle, and their immune systems are likely to be weaker, once deprived of human antibiotics and the like. Good point about predators, but even that is our responsibility. We have made their numbers artificially high, and there would come reckoning. — Ben Barden, Jun 27 '17 at 13:35
@Ben Barden: I disagree that the numbers are artificially high. They are concentrated in particular places for human convenience, yet for the same reason have been removed from large areas they (or wild relatives like buffalo) would naturally inhabit. So instead of millions of buffalo grazing the Great Plains, cattle are concentrated in feedlots, the plains are turned into hay & grain fields, and feed is harvested & transported (using fossil fuels!) to the cattle. — jamesqf, Jun 28 '17 at 16:23
@Ben Barden: On long-term cattle survival in the wild, not all cows are the same. Hereabouts there are a lot of open range cattle which fend for themselves during most of the year, and are rounded up in the fall. Some are missed in the roundup, and do manage to over-winter. These cattle would survive & reproduce absent human intervention. We already have a good example - wild horses - which survive & reproduce in the wild. Indeed, it's gone full-circle: many people (I'm one) ride mustangs captured from the wild/feral population. — jamesqf, Jun 28 '17 at 16:30
err. Cows make Carbon dioxide by breathing, and methane by chewing. In fact all mammals breath whilst alive. — mckenzm, Jan 29 '18 at 20:51
It's extremely naive to believe cows wouldn't exist if not for humans. Just like pigs, or horses, a herd of cows would become wild, and likely survive in the wild, just as bison did in the Americas prior to the Europeans settling here. — Keith, Apr 30 '19 at 15:46

Kevin Fee · Accepted Answer · 2017-06-26T15:28:44.143

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TLDR: Yes. Cows produce around 9.5% of human originated pollution, or greenhouse gases (GHGs), while cars produce around 8.5% of human originated GHGs. This does not mean that humans shouldn't be blamed for climate change, however, as 85.5% of GHGs do not come from domestic animals.

Regardless of whether two cows produce as much greenhouse gas as a car, we have a lot of other polluters:

Let's take a look at the United States according to the US's EPA:

Digging down further into their numbers for Agriculture, enteric fermentation ("cow belching", or more accurately, all livestock emissions) makes up one third of the numbers for "Agriculture", which in the US is only 9% of the greenhouse emissions. Mostly it's farming that introduces greenhouse gases in agriculture.

If we look at the worldwide emissions, also on the EPA's site:

Here, agriculture & forestry together produce less than a quarter of pollution, and that includes deforestation.

They also note that, while they don't include it in the graph, the biosphere, or natural carbon cycle, offsets only 20% of the agricultural output, or 4.8% of anthropogenic GHGs. I shall not include it in my calculations as it is a global effect, not specific to cows.

According to the Food and Agricultural Organization of the United Nations, Livestock in its entirety produces 14.5% of total greenhouse gas emissions, as opposed to transportation (car, truck, airplanes) taking 14%. It also notes that cows are responsible for 65% of those emissions, for a total of 9.45% of emissions. As for cars, according to the EPA once again, "light duty vehicles" (ie, cars) make up 61% of transportation emissions, for a total of 8.54% of total emissions. So in that view, yes, cows produce more total emissions than cars, but this doesn't mean that cows are more to blame than humanity for climate change.

edited Jun 26 '17 at 15:28

answered Jun 23 '17 at 19:20

Kevin Fee

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Kevin, I'll delete my answer since yours is similar. This is my other reference http://www.fao.org/news/story/en/item/197623/icode/ in case you want to add it. – DavePhD Jun 23 '17 at 19:35
This doesn't answer my question directly. I need Yes or No answer. – Grasper Jun 23 '17 at 19:41
@Grasper "If this is true humans shouldn't be blamed for the climate change." is what I answered, which is "NO." Since agriculture doesn't even account for a quarter of global pollution, and that's all you can even tenuously blame on cows, no, cows aren't to blame for climate change. – Kevin Fee Jun 23 '17 at 19:46
@KevinFee, sorry, the question was "Do cows produce more CO2 than cars?" not the one you stated. – Grasper Jun 23 '17 at 19:49
@Grasper even your graphic doesn't say that. It says a cow produces *half* as much as a car. – Kevin Fee Jun 23 '17 at 19:53
@KevinFee Is that 14.5% inclusive of livestock production -- producing, processing and transporting feed; processing and transporting meat and dairy? Cause if you just say "livestock" it sounds like some cow sitting in a meadow is participating in our doom. – jeffronicus Jun 23 '17 at 20:20
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@jeffronicus That includes feed production and land change, as well as enteric fermentation and manure, and processing of the animal products. About 94% of the livestock number is "sitting around in a meadow participating in our doom", though, through eating, flatulence, manure, and exhaling. 6% is in processing, and 45% is simply in feeding them, with 39% is cow emmissions and 10% is cow excretions. – Kevin Fee Jun 23 '17 at 20:31
I thought cattle greenhouse emissions was from burping, not farting. – Andrew Grimm Jun 23 '17 at 23:42
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This answer is wrong (and the "explanation" in the question is intentionally designed to mislead). What cows and other animals (including humans) produce is part of the natural carbon cycle, which is stable over the long term. (That is, critters have been exhaling for hundreds of millions of years, without causing problems.) What cars emit is produced from buried carbon (unless you run on biofuel of some sort), and so is ADDING CO2 to the atmosphere. – jamesqf Jun 24 '17 at 04:44
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FYI, when I read "pollution" I don't think "CO2", I think "NOX". (I've never thought of cows as pollution agents.) A more accurate term might be better... – user541686 Jun 24 '17 at 08:32
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@jamesqf You are incorrect. As I noted from the EPA website, 20% of human agriculture output is offset by the natural carbon cycle. We aren't adding trees or other CO2 scrubbing organisms to offset our increase in animals. In fact, we're taking them away. In the past, when there were more "critters" that produced more CO2, it provided more for the CO2 scrubbers to feed on, and so they flourished. We've been doing our best to curtail them because they encroach on our space. – Kevin Fee Jun 26 '17 at 15:06
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@AndrewGrimm Good point, it's actually about any and all emissions, but it is usually called cow burps. Fixed. – Kevin Fee Jun 26 '17 at 15:24
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@Mehrdad I mostly used "greenhouse emissions", but I've gone ahead and removed all but one mention of pollution, and in that mention I simply use it to clarify that I'm specifically talking about GHGs. – Kevin Fee Jun 26 '17 at 15:27
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@Kevin Fee: You are misreading that EPA info. That carbon/GHG output from the agricultural sector includes all the fossil fuels used, plus the effects of land use changes &c. We are not increasing the total number of animals, just shifting the balance between a handful of domesticated species, and all the other "wild" ones. – jamesqf Jun 27 '17 at 05:15
https://xkcd.com/1338/ – Scrontch Jun 29 '17 at 13:04
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@jamesqf Not commenting on Kevin Fee answer. However, you are hugely ignorant if you think that the biomass ratio of producers to consumers, the biomass ratio of different trophic levels and the total biomass on Earth hasnt changed over time because of animal agriculture. – y chung Jul 22 '17 at 06:07
@y chung : Got data to support that? Logically, it pretty well has to be the same overall (barring some removal of buried carbon, which is a slow process), otherwise there would be big piles of unconsumed biomass sitting around. – jamesqf Jul 23 '17 at 17:00

score 3 · Answer 2 · answered Dec 23 '19 at 17:11

If this is true humans shouldn't be blamed for the climate change. I understand we grow them for meat so it's again us. But if we would let the cows overpopulate we would end up with the same result.

Cows would not naturally appear in this population if it would not be us breeding them (using fossile fuels to mass-produce soja, harvest protein from the sea to feed cows and artificially inseminating them to even reproduce under stressful conditions while locked up in cages). The ecological footprint caused by is mainly caused by humans.

So, yes, humans are the main factor here, even if it goes via the cows and not the cars....

Do cows contribute more to atmospheric warming than cars?

2 Answers2